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Silicate minerals
The silicate minerals make up the largest and most important class of rock-forming minerals, constituting approximately 90 percent of the crust of the Earth. They are classified based on the structure of their silicate group which contain different ratios of silicon and oxygen. ]] Nesosilicates or orthosilicates Nesosilicates (from Greek νησος nēsos, island), or orthosilicates, have isolated (insular) SiO44− tetrahedra that are connected only by interstitial cations. Nickel-Strunz classification: 09.A *Phenakite group **Phenakite - Be2SiO4 **Willemite - Zn2SiO4 *Olivine group **Forsterite - Mg2SiO4 **Fayalite - Fe2SiO4 *Garnet group **Pyrope - Mg3Al2(SiO4)3 **Almandine - Fe3Al2(SiO4)3 **Spessartine - Mn3Al2(SiO4)3 **Grossular - Ca3Al2(SiO4)3 **Andradite - Ca3Fe2(SiO4)3 **Uvarovite - Ca3Cr2(SiO4)3 **Hydrogrossular - Ca3Al2Si2O8(SiO4)3-m(OH)4m *Zircon group **Zircon - ZrSiO4 **Thorite - (Th,U)SiO4 crystals (unknown scale)]] *Al2SiO5 group **Andalusite - Al2SiO5 **Kyanite - Al2SiO5 **Sillimanite - Al2SiO5 **Dumortierite - Al6.5-7BO3(SiO4)3(O,OH)3 **Topaz - Al2SiO4(F,OH)2 **Staurolite - Fe2Al9(SiO4)4(O,OH)2 *Humite group - (Mg,Fe)7(SiO4)3(F,OH)2 **Norbergite - Mg3(SiO4)(F,OH)2 **Chondrodite - Mg5(SiO4)2(F,OH)2 **Humite - Mg7(SiO4)3(F,OH)2 **Clinohumite - Mg9(SiO4)4(F,OH)2 *Datolite - CaBSiO4(OH) *Titanite - CaTiSiO5 *Chloritoid - (Fe,Mg,Mn)2Al4Si2O10(OH)4 Sorosilicates Sorosilicates (from Greek σωρός sōros, heap, mound) have isolated double tetrahedra groups with (Si2O7)6− or a ratio of 2:7. Nickel-Strunz classification: 09.B *Hemimorphite (calamine) - Zn4(Si2O7)(OH)2·H2O *Lawsonite - CaAl2(Si2O7)(OH)2·H2O *Ilvaite - CaFe2+2Fe3+O(Si2O7)(OH) *Epidote group (has both (SiO4)4− and (Si2O7)6− groups) **Epidote - Ca2(Al,Fe)3O(SiO4)(Si2O7)(OH) **Zoisite - Ca2Al3O(SiO4)(Si2O7)(OH) **Clinozoisite - Ca2Al3O(SiO4)(Si2O7)(OH) **Tanzanite - Ca2Al3O(SiO4)(Si2O7)(OH) **Allanite - Ca(Ce,La,Y,Ca)Al2(Fe2+,Fe3+)O(SiO4)(Si2O7)(OH) **Dollaseite-(Ce) - CaCeMg2AlSi3O11F(OH) *Vesuvianite (idocrase) - Ca10(Mg,Fe)2Al4(SiO4)5(Si2O7)2(OH)4 Cyclosilicates Cyclosilicates (from Greek κύκλος kuklos, circle), or ring silicates, have linked tetrahedra with (TxO3x)2x- or a ratio of 1:3. These exist as 3-member (T3O9)6- and 6-member (T6O18)12- rings, where T stands for a tetrahedrally coordinated cation. Nickel-Strunz classification: 09.C * 3-member ring ** Benitoite - BaTi(Si3O9) * 6-member ring **Axinite - (Ca,Fe,Mn)3Al2(BO3)(Si4O12)(OH) **Beryl/Emerald - Be3Al2(Si6O18) **Cordierite - (Mg,Fe)2Al3(Si5AlO18) **Tourmaline - (Na,Ca)(Al,Li,Mg)3-(Al,Fe,Mn)6(Si6O18(BO3)3(OH)4 Note that the ring in axinite contains two B and four Si tetrahedra and is highly distorted compared to the other 6-member ring cyclosilicates. File:Beryll.ring.combined.png|Cyclosilicate, Si6O18- 6-membered single rings, beryl (red: Si, blue: O) File:Benitoid.2200.png|Cyclosilicate, Si3O9- 3-membered single ring, benitoite File:Papagoite.2200.png|Cyclosilicate, Si4O12- 4-membered single ring, papagoite File:Eudialyte.2200.png|Cyclosilicate, Si9O27- 9-membered ring, eudialyte File:Milarite.png|Cyclosilicate, Si6O18- 6-membered double ring, milarite Inosilicates Inosilicates (from Greek ις is [genitive: ινος inos], fibre), or chain silicates, have interlocking chains of silicate tetrahedra with either SiO3, 1:3 ratio, for single chains or Si4O11, 4:11 ratio, for double chains. Nickel-Strunz classification: 09.D Single chain inosilicates *Pyroxene group **Enstatite - orthoferrosilite series ***Enstatite - MgSiO3 ***Ferrosilite - FeSiO3 **Pigeonite - Ca0.25(Mg,Fe)1.75Si2O6 **Diopside - hedenbergite series ***Diopside - CaMgSi2O6 ***Hedenbergite - CaFeSi2O6 ***Augite - (Ca,Na)(Mg,Fe,Al)(Si,Al)2O6 **Sodium pyroxene series ***Jadeite - NaAlSi2O6 ***Aegirine (Acmite) - NaFe3+Si2O6 **Spodumene - LiAlSi2O6 *Pyroxenoid group **Wollastonite - CaSiO3 **Rhodonite - MnSiO3 **Pectolite - NaCa2(Si3O8)(OH) Double chain inosilicates *Amphibole group **Anthophyllite - (Mg,Fe)7Si8O22(OH)2 **Cumingtonite series ***Cummingtonite - Fe2Mg5Si8O22(OH)2 ***Grunerite - Fe7Si8O22(OH)2 **Tremolite series ***Tremolite - Ca2Mg5Si8O22(OH)2 ***Actinolite - Ca2(Mg,Fe)5Si8O22(OH)2 **Hornblende - (Ca,Na)2-3(Mg,Fe,Al)5Si6(Al,Si)2O22(OH)2 **Sodium amphibole group ***Glaucophane - Na2Mg3Al2Si8O22(OH)2 ***Riebeckite (asbestos) - Na2Fe2+3Fe3+2Si8O22(OH)2 ***Arfvedsonite - Na3(Fe,Mg)4FeSi8O22(OH)2 File:Pyroxen-chain.png|Inosilicate, pyroxene family, with 2-periodic single chain (Si2O6), diopside File:Tremolite-chain.png|Inosilicate, clinoamphibole, with 2-periodic double chains (Si4O11), tremolite File:Wollastonite-chain.png|Inosilicate, unbranched 3-periodic single chain of wollastonite File:Rhodonite-chain.png|Inosilicate with 5-periodic single chain, rhodonite File:Pellyite-chain.png|Inosilicate with cyclic branched 8-periodic chain, pellyite Phyllosilicates Phyllosilicates (from Greek φύλλον phyllon, leaf), or sheet silicates, form parallel sheets of silicate tetrahedra with Si2O5 or a 2:5 ratio. Nickel-Strunz classification: 09.E The word comes from the Greek word phyllon, which means "leaf".Essentials of Geology, 3rd Ed, Stephen Marshak *Serpentine group **Antigorite - Mg3Si2O5(OH)4 **Chrysotile - Mg3Si2O5(OH)4 **Lizardite - Mg3Si2O5(OH)4 *Clay mineral group **Halloysite - Al2Si2O5(OH)4 **Kaolinite - Al2Si2O5(OH)4 **Illite - (K,H3O)(Al,Mg,Fe)2(Si,Al)4O10(OH)2,(H2O) **Montmorillonite - (Na,Ca)0.33(Al,Mg)2Si4O10(OH)2·''n''H2O **Vermiculite - (MgFe,Al)3(Al,Si)4O10(OH)2·4H2O **Talc - Mg3Si4O10(OH)2 **Palygorskite - (Mg,Al)2Si4O10(OH)·4(H2O) **Pyrophyllite - Al2Si4O10(OH)2 *Mica group **Biotite - K(Mg,Fe)3(AlSi3)O10(OH)2 **Muscovite - KAl2(AlSi3)O10(OH)2 **Phlogopite - KMg3(AlSi3)O10(OH)2 **Lepidolite - K(Li,Al)2-3(AlSi3)O10(OH)2 **Margarite - CaAl2(Al2Si2)O10(OH)2 **Glauconite - (K,Na)(Al,Mg,Fe)2(Si,Al)4O10(OH)2 *Chlorite group **Chlorite - (Mg,Fe)3(Si,Al)4O10(OH)2•(Mg,Fe)3(OH)6 File:Muskovite.sheet.png|Phyllosilicate, mica group, muscovite (red: Si, blue: O) File:Apophyllite.sheet.png|Phyllosilicate, single net of tetrahedra with 4-membered rings, apophyllite-(KF)-apophyllite-(KOH) series File:Pyrosmalite.sheet.png|Phyllosilicate, single tetrahedral nets of 6-membered rings, pyrosmalite-(Fe)-pyrosmalite-(Mn) series File:Zeophyllite.sheet.png|Phyllosilicate, single tetrahedral nets of 6-membered rings, zeophyllite File:Carletonite.sheet.png|Phyllosilicate, double nets with 4- and 6-membered rings, carletonite Tectosilicates Tectosilicates, or "framework silicates," have a three-dimensional framework of silicate tetrahedra with SiO2 or a 1:2 ratio. This group comprises nearly 75% of the crust of the Earth. Tectosilicates, with the exception of the quartz group, are aluminosilicates. Nickel-Strunz classification: 09.F and 09.G, 04.DA (Quartz/ silica family) ]] Ferroan Anorthosite #60025 (Plagioclase Feldspar). Collected by Apollo 16 from the Lunar Highlands near Descartes Crater. ]] *Quartz group **Quartz - SiO2 **Tridymite - SiO2 **Cristobalite - SiO2 **Coesite - SiO2 *Feldspar family **Alkali-feldspars (potassium-feldspars) ***Microcline - KAlSi3O8 ***Orthoclase - KAlSi3O8 ***Anorthoclase - (Na,K)AlSi3O8 ***Sanidine - KAlSi3O8 ***Albite - NaAlSi3O8 **Plagioclase feldspars ***Albite - NaAlSi3O8 ***Oligoclase - (Na,Ca)(Si,Al)4O8 (Na:Ca 4:1) ***Andesine - (Na,Ca)(Si,Al)4O8 (Na:Ca 3:2) ***Labradorite - (Na,Ca)(Si,Al)4O8 (Na:Ca 2:3) ***Bytownite - (Na,Ca)(Si,Al)4O8 (Na:Ca 1:4) ***Anorthite - CaAl2Si2O8 *Feldspathoid family **Nosean - Na8Al6Si6O24(SO4) **Cancrinite - Na6Ca2(CO3,Al6Si6O24).2H2O **Leucite - KAlSi2O6 **Nepheline - (Na,K)AlSiO4 **Sodalite - Na8(AlSiO4)6Cl2 ***Hauyne - (Na,Ca)4-8Al6Si6(O,S)24(SO4,Cl)1-2 **Lazurite - (Na,Ca)8(AlSiO4)6(SO4,S,Cl)2 *Petalite - LiAlSi4O10 *Scapolite group **Marialite - Na4(AlSi3O8)3(Cl2,CO3,SO4) **Meionite - Ca4(Al2Si2O8)3(Cl2CO3,SO4) *Analcime - NaAlSi2O6•H2O *Zeolite family **Natrolite - Na2Al2Si3O10•2H2O **Chabazite - CaAl2Si4O12•6H2O **Heulandite - CaAl2Si7O18•6H2O **Stilbite - NaCa2Al5Si13O36•17H2O **Scolecite - CaAl2Si3O10.3H2O **Mordenite - (Ca,Na2,K2)Al2Si10O24•7H2O Gallery File:Silicate-tetrahedron-3D-balls.png|Nesosilicate (SiO4) File:Silicate-double-tetrahedra-3D-balls.png|Sorosilicate (Si2O7), as in suolunite Ca2Si2O5(OH)2·H2O File:Zeolite-ZSM-5-3D-vdW.png|Tectosilicate, aluminosilicate 3-D network, zeolite family, synthetic zeolite ZSM-5 File:Beta-quartz-CM-2D-balls.png|Silica family (SiO2 3-D-network), β-quartz See also * Classification of minerals - Non silicates * Classification of minerals - Silicates * Silicate mineral paint References * * * * *Mindat.org, Dana classification *Webmineral : Dana's New Silicate Classification External links ar:معادن السيليكات ca:Mineral silicat de:Silikate eo:Silikatmineraloj fa:کانی‌های سیلیکات fr:Silicate mk:Силикатни минерали ja:ケイ酸塩鉱物 pt:Silicato (minerais) Category:Mineralogy